Satan is an embodiment of antagonism that originates from the Abrahamic religions. Since then, those religions have used Satan to refer to the Devil.
In an effort to reunite their mothers in "A Roger Story", Steve and Snot die and go to Hell when Roger confuses a temporary acting poison for a more permanent one. In an effort to recover the boys, Roger escorts Francine and Esther Lonstein to Hell via an elevator located in Sub Hub. Satan agrees to free the boys, but insists that the mothers stick to their vow to stay together forever and keeps them in Hell.